Warning: This page is not a guide to
making fireworks. Fireworks are complex devices that require great care to
make, not only so they perform properly, but also to avoid a potentially fatal
accident. The following information is to help readers learn more about
how fireworks function by understanding how the devices are created. For
that reason, no specific chemical formulas are listed in this section.

ROLLING and PLUGGING TUBES

Fireworks tubes are made by rolling thick
paper tightly around a former, such as a dowel. Though they can be
made by hand, most firework/tube factories use machinery to manufacture
tubes.

Whenever tubes are used in fireworks, at
least one end is always plugged with clay to keep both chemicals and
burning gases from escaping through that end. The tooling is always
made of non-sparking materials such as aluminum or brass. Clay is
inserted into the tube and then consolidated with the rammer using a heavy
object such as a mallet (or possibly a fruit cake). A sleeve is
sometimes used during the ramming process to prevent the walls of the tube
from splitting or bulging. This process is illustrated below.

AERIAL REPEATER

1. To make a typical square-shaped repeater, several
clay-rammed tubes are glued to each other in rows. Often a
"sandwich" is made by placing thin cardboard strips on either
sides of the tubes for strength.

2. Two holes are then drilled in each tube. Small pieces of
fuse are placed in the holes to rapidly transfer fire from tube to tube.

3. Rows of tubes are glued on top of each other, and fuses are
inserted to transfer fire between rows.

4. The battery of tubes is then stood upright, and a
small, measured black powder lifting charge is put into each tube.
After that, a small tube containing aerial effects (stars, whistles,
hummers, etc.) is placed into each larger tube. To see a cross
section of what this looks like, click
here. Yes, I do have too much spare time.

5. Finally, the bottom and sides of the repeater are covered in
another layer of thin cardboard to hold it together, followed (usually) by
plastic cellophane on top and a colorful label on the side.

FOUNTAIN

Fountains consist of a tube filled with composition with
clay plugs on either end, one of which has a small hole in it (see
below). The hole, called a "choke", prevents the hot gas
from escaping from the tube as easily as it would if there were no plug at
all. This builds up pressure inside the tube, and as a result
escaping gas and sparks are shot up with a lot of force.

The easiest way of making a choke is to build it directly into the
fountain tube by compacting clay around a former known as a nipple.
Solid rammers are used to compress the fountain composition once it has
been inserted into the tube. Nipples usually have a sleeve that the
tube fits in to prevent it from breaking when the composition is being
rammed in. All fountain tooling should be made of non-sparking
materials such as aluminum, brass, or wood.

If you don't understand any of the stuff above, just scroll down and
let my award-winning MS Paint drawings explain it to you visually.

PROCESS

1. A tube is placed in the spindle/sleeve assembly and
an amount of clay is added.
2. The rammer with the small indent is used to compact the clay around the
spindle, which leave create a hole when the tube is eventually removed. The
clay plug should always be as thick as the tube is wide.
3. After the choke is formed, increments of fountain composition (the
grayish stuff) are added in small increments and compacted with the
solid rammer. This process is repeated until the tube is nearly full.
4. When little room remains at the top of the tube, more clay is
added/compacted to make another plug.

5. The tube is removed from the nipple/sleeve assembly and inverted.
It is then attached to a block of wood (see below) and a fuse is inserted into
the choke. Usually thin kraft "nosing paper" is pasted on the
tube so that it overlaps the top end of the fountain, which serves to protect
the fuse.

Multiple-tube fountains are becoming more and more common these days as
consumer fireworks continue to get bigger and better. Such
fountains aren't actually one unit, but consist of many fountains fused
together within a large tube (shown at right). In most cases, the
outer casing is large enough to support the device without it needed any
sort of base.